package com.hengpeng.msls.util;
import java.io.IOException;
import java.security.SecureRandom;
import java.util.HashMap;
import java.util.Map;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class EncrypDES{

	private final static String DES = "DES";

	public static void main(String[] args) throws Exception
	{
		String password = "sessionId=6d717da8ff00ff114d72b3428434511c&uid=123&cityCode=&uChannel=001&uRole=000";
		try
		{
			String crypter = EncryptAndDecryptPin("0002013531008000", password, 1);
			System.out.println("加密后的数据：" + crypter);
			String clear = EncryptAndDecryptPin("0002013531008000", crypter, 0);
			Map<String, String> map = new HashMap<String, String>();
			String str[] = clear.split("&");
			for (int i = 0; i < str.length; i++)
			{
				String va = str[i];
				map.put(va.substring(0, va.indexOf("=")), va.substring(va.indexOf("=") + 1));
			}
			System.out.println(map.get("uid"));
			System.out.println("解密后的数据：" + clear);

		}
		catch (Exception ex)
		{
			System.out.println(ex);
		}
	}

	/**
	 * @param key: 密钥值
	 * @param pin: 明文或密文
	 * @param model: 1时表示加密， 0时表示为解密
	 * @return
	 */
	public static String EncryptAndDecryptPin(String key, String pin, int model)
	{
		String strData = "";
		try
		{
			if (1 == model)
			{
				strData = encrypt(pin, key);
			}
			else if (0 == model)
			{
				strData = decrypt(pin, key);
			}
		}
		catch (Exception e)
		{
			e.printStackTrace();
		}

		return strData;

	}

	/**
	 * Description 根据键值进行加密
	 * @param data
	 * @param key 加密键byte数组
	 * @return
	 * @throws Exception
	 */

	public static String encrypt(String data, String key) throws Exception
	{

		byte[] bt = encrypt(data.getBytes(), key.getBytes());

		String strs = new BASE64Encoder().encode(bt);

		return strs;

	}

	/**
	 * Description 根据键值进行解密
	 * @param data
	 * @param key 加密键byte数组
	 * @return
	 * @throws IOException
	 * @throws Exception
	 */

	public static String decrypt(String data, String key) throws IOException,

	Exception
	{

		if (data == null)

			return null;

		BASE64Decoder decoder = new BASE64Decoder();

		byte[] buf = decoder.decodeBuffer(data);

		byte[] bt = decrypt(buf, key.getBytes());

		return new String(bt);

	}

	/**
	 * Description 根据键值进行加密
	 * @param data
	 * @param key 加密键byte数组
	 * @return
	 * @throws Exception
	 */

	private static byte[] encrypt(byte[] data, byte[] key) throws Exception
	{

		// 生成一个可信任的随机数源

		SecureRandom sr = new SecureRandom();

		// 从原始密钥数据创建DESKeySpec对象

		DESKeySpec dks = new DESKeySpec(key);

		// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象

		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);

		SecretKey securekey = keyFactory.generateSecret(dks);

		// Cipher对象实际完成加密操作

		Cipher cipher = Cipher.getInstance(DES);

		// 用密钥初始化Cipher对象

		cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);

		return cipher.doFinal(data);

	}

	/**
	 * Description 根据键值进行解密
	 * @param data
	 * @param key 加密键byte数组
	 * @return
	 * @throws Exception
	 */

	private static byte[] decrypt(byte[] data, byte[] key) throws Exception
	{

		// 生成一个可信任的随机数源

		SecureRandom sr = new SecureRandom();

		// 从原始密钥数据创建DESKeySpec对象

		DESKeySpec dks = new DESKeySpec(key);

		// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象

		SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);

		SecretKey securekey = keyFactory.generateSecret(dks);

		// Cipher对象实际完成解密操作

		Cipher cipher = Cipher.getInstance(DES);

		// 用密钥初始化Cipher对象

		cipher.init(Cipher.DECRYPT_MODE, securekey, sr);

		return cipher.doFinal(data);

	}
	
}
